反射镜柔性支撑结构的模态参数分析

Modal analysis of flexural support system for reflect mirrors

为解决全面、准确地检测反射镜柔性支撑结构的柔度参数的问题,将参数辨识技术应用到柔度测试领域中。开展了在频域中基于模态参数辨识理论分析柔性支撑结构柔度参数的分析。首先,对于串联弹簧-质量-阻尼系统的传递函数及其性质进行了推导,建立了一种对于串联模型端部子系统参数进行辨识的方法;然后,利用计算机进行了数值仿真,以验证上述理论推导的准确性;最后,针对某小型反射镜的柔性支撑结构Bipod进行了实验验证。实验结果表明,该测试方法与传统的测量方法相比误差小于5%,证明了该方法的可行性,对其他柔性部件的检测分析都有较好的指导意义。

Aiming at the problems of measuring comprehensively and exactly the flexibility parameters of the flexural support system for reflect mirror,the parameter identification was investigated and the modal parameter identification theory was introduced in the frequency domain to analyze the flexibility parameters of the flexural support system. Firstly, the spring-mass-dumping modal in series was built to study the flexural support system in certain direction and get the methods approach to the parameter of the free side sub-system by the transfer matrix of the overall system. Then, after the analysis of numerical emulation, the correctness of the research mentioned above was evaluated. At the last, it was tested by use of the special flexural support system, Bipod for instance, for small reflect mirrors. The experimental results indicate that compared with experiment error between researched method and traditional way are smaller than 5%, which indicate that it is rational and accurate, can act as the reference of the measurement and analysis for other flexible system.